1. Field of the Invention
The invention relates to a heat-sealed type monoblock storage battery adapted for use in automobiles and similar devices.
2. Description of Pertinent Information
One type of storage battery comprises a battery container and a cover. The container comprises a plurality of cell chambers formed by partitioning the interior of a battery container with a plurality of partition walls. Each chamber comprises a cell or electrode plate assembly. Each cell comprises a plurality of negative plates and a row of tabs protruding from the upper edges of the negative plates. A strap, called a negative strap because it is attached to the negative plates, interconnects the tabs. Each cell and electrode plate assembly also comprises a plurality of positive plates and a row of tabs protruding from the upper edges of the positive plates. A strap called a positive strap, interconnects the positive tabs.
A positive strap from one cell is connected to a negative strap from a mutually adjacent cell by intercell connecting conductors which extend through a hole in the partition wall separating the adjacent cells. Each intercell connecting conductor comprises a horizontal base and an ear extending upwardly from the horizontal base so as to face the hole in the partition wall. One of the negative straps is used as a negative terminal. This strap is provided with a negative terminal post extending upwardly from this negative strap. Similarly, one of the positive straps is used as a positive terminal. This strap is provided with a positive terminal post extending upwardly from the positive strap.
The battery cover has a box-like shape which is adapted to cover the battery container. The cover comprises a top wall, a downwardly extending peripheral side wall extending downwardly from the top wall, and downwardly extending partition walls which partition the inside space of the battery cover. The side and partition walls are adapted to be brought into contact with and hermetically adhered to a peripheral side wall and the partition walls, respectively, of the battery container. The top wall of the cover also comprises negative and positive terminal settling holes adapted to receive therethrough the upper part of the negative and positive posts, respectively, and the top wall further comprises negative and positive terminal settling surface regions surrounding the negative and positive terminal settling holes, respectively. Furthermore, the positive and negative posts are adapted to extend through these settling holes to the outside of the battery to form a positive and a negative terminal on respective terminal settling surface regions of the top wall of the cover.
Such a known battery is illustrated in FIGS. 1 and 2. This battery will now be discussed with respect to these two figures.
The battery illustrated in FIGS. 1 and 2 comprises a battery container A comprising a plurality of partition walls B which form a plurality of cell chambers C. Within each of the cell chambers is formed a cell D. Each cell comprises an electrode plate assembly including a plurality of negative electrodes and a plurality of tabs E forming a row. Each tab E is attached to a negative electrode. Each cell also comprises a plurality of positive electrodes and a row of tabs F attached to the positive electrodes. Also provided in each cell are strap G and strap H. Strap G connects negative tabs E, and therefore strap G is called a negative strap. Similarly, strap H connects the positive tabs F and is therefore called a positive strap. Straps G and H of adjacent cells are aligned with one another on either side of a partition wall B separating adjacent cells D, D. In addition, the battery also comprises intercell connecting conductors which connect straps G and H. The conductors comprise horizontal base parts I, I which project horizontally and laterally, that is inwardly, from straps G and H. In addition, the intercell connecting conductors also comprise ear portions K, K which extend vertically upward from base parts I, I so as to extend along and close to opposite sides of partition wall B. These ears K, K of each intercell connecting conductor in adjacent cells face each other through a perforation hole or opening M in partition wall B. Ears K, K in adjacent cells are connected to each other through hole M by means of an electric welding. This is accomplished by applying a forward portion P of a welding gun to ear portions K, K, or by using any other desired connecting means. In addition, the battery further comprises a battery cover Q and negative and positive terminals R, R', respectively.
This storage battery has serious disadvantages which arise from the extending of ears K, K directly above base portions I, I, and because of the alignment of opening M with the upper portions of ears K, K. As a result of this positioning of these elements, when ears K, K are welded by a welding gun the forward end P of the welding gun contacts the upper surfaces of horizontal bases I, I which are located directly below ears K, K.
In order to prevent this undesireable welding of horizontal bases I, I, the distance between base portion I and perforation M can be increased by increasing the height h of ears k, k. However, this increasing of the height h of ears K, K of the intercell connecting conductors from base portion I to hole M causes other problems because the height of partition wall B must also be increased, thereby increasing the height of the storage battery. This is undesireable, particularly when such a storage battery is used in an automobile, where space is at a premium.
In addition, the above-discussed storage battery also has another disadvantage. The type of storage battery discussed above is made in such a manner that the battery container and the box-like battery cover are fused together at mutually abutting edges of their entire peripheral side walls in the same horizontal plane. As a result, the negative and positive terminal post settling holes in the top wall of the battery cover are positioned higher than the upper horizontal edges of the partition walls of the battery container. Thus, the space between the negative and positive terminal straps and the negative and positive terminal settling surface regions of the top wall of the battery cover, respectively, is comparatively large and the length of the negative and positive terminal posts from each corresponding strap to each respective negative and positive terminal settling hole is also comparatively large. Consequently, each terminal has a comparatively large electrical resistance thereby diminishing the amount of current that can be taken out from each terminal.
Thus, there is a need for a storage battery in which the positive and negative terminal posts of the battery are as small as practically possible, and in which the ears of the intercell connecting conductors are so positioned that the welding gun used to weld the intercell connecting conductors together does not contact the horizontal base portions of the conductor, without increasing the height of the battery.